The present invention relates to the field of diamond enhanced valves. The prior art discloses diamond coatings or films on valve surfaces deposited by vapor deposition. Diamond is grown in a vapor deposition process by disposing a substrate in an environment that encourages diamond grain growth. The substrate may be exposed to gases comprising carbon and hydrogen. These gases may be deposited onto the substrate causing grain growth. The vapor deposition process may occur under low pressure, between one and twenty seven kPa. The diamond formed by chemical vapor deposition may comprise anisotropic properties, properties with different values when measured in different directions. The diamond grains may also be loosely bonded to one another as the process occurs at low pressure.
U.S. Pat. No. 5,040,501 to Lemelson, which is herein incorporated by reference for all that is contains, discloses valves. In one form, a select portion of the surface of a valve component or components subject to degradation during use such as erosive and/or corrosive effects of fluid particles and liquid or vaporous fluid passing through the valve, is coated with a synthetic diamond material which is formed in situ thereon. In another form, the entire surface of the valve component is so coated. The component may be a movable poppet member for an exhaust valve for a combustion chamber of an internal combustion piston engine. The valve seat or insert may also be coated with synthetic diamond material, particularly the circular tapered inside surface thereof against which a portion of the underside of the head of the valve poppet which engages the seat when the valve is spring closed. By coating the entire head and stem of the valve poppet with synthetic diamond and overcoating or plating a solid lubricant, such as chromium on the outer surface of the diamond coating a number of advantages over conventional valve construction are derived including better heat and corrosion resistance, reduced wear resulting from seat and valve head impact contact and a reduction in the enlargement of surface cracks. Similar improvements are effected for the valve seat when so coated and protected. In a modified form, the entire interior or selected portions of the wall of the valve body or the combustion chamber containing the valve may be coated with synthetic diamond material with or without a protective overcoating.